2 // Copyright 2019 Mateusz Loskot <mateusz at loskot dot net>
4 // Distributed under the Boost Software License, Version 1.0
5 // See accompanying file LICENSE_1_0.txt or copy at
6 // http://www.boost.org/LICENSE_1_0.txt
8 #include <boost/gil/color_base_algorithm.hpp>
9 #include <boost/gil/pixel.hpp>
10 #include <boost/gil/typedefs.hpp>
15 namespace gil = boost::gil;
19 // K-element index must be less than size of channel_mapping_t sequence
20 // of the *destination* color base.
22 // RGB (wider space) transformation to Gray (narrower space) takes only R channel value
24 gil::cmyk8_pixel_t src{16, 32, 64, 128};
25 gil::rgb8_pixel_t dst{0, 0, 0};
26 gil::static_transform(src, dst, [](std::uint8_t src_channel) {
27 return src_channel; // copy
29 assert(gil::at_c<0>(dst) == std::uint16_t{16});
30 assert(gil::at_c<0>(dst) == std::uint16_t{32});
31 assert(gil::at_c<0>(dst) == std::uint16_t{64});
34 // RGB (narrower space) to CMYK (wider space) transformation FAILS to compile
36 gil::rgb8_pixel_t src{16, 32, 64};
37 gil::cmyk8_pixel_t dst{0, 0, 0, 0};
38 gil::static_transform(src, dst, [](std::uint8_t src_channel) {
39 return src_channel; // copy